Question

A number of tunable DBR lasers are available. We want to have a source of light available anywhere in C band (1,530 - 1,565 nm). Suppose the range over which we can tune the effective refractive index by heating the Bragg region is 0.8 % (or 0.008) How many different lasers (each having a different center wavelength) do we need to purchase? Hint: the proper tuning range should be selected by the smallest tuning range.

Answer 1

To cover the C band range of 1,530 - 1,565 nm, you would need to purchase at least 44 different lasers with different center wavelengths.

Step-by-step explanation:

In order to have a source of light available anywhere in the C band (1,530 - 1,565 nm), we need to purchase different lasers with different center wavelengths. The tuning range of the effective refractive index is 0.8%, or 0.008. To determine the number of lasers needed, we divide the tuning range of the C band (35 nm) by the tuning range of the refractive index (35 nm * 0.008) to account for the smallest tuning range. This gives us approximately 43.75, so we would need to purchase at least 44 different lasers to cover the desired range.